Nano-second exciton-polariton lasing in organic microcavities

Organic semiconductors are a promising platform for ambient polaritonics. Several applications, such as polariton routers, and many-body condensed matter phenomena are currently hindered due to the ultra-short polariton lifetimes in organics. Here, we employ a single-shot dispersion imaging technique, using 4 ns long non-resonant excitation pulses, to study polariton lasing in a λ/2 planar organic microcavity filled with BODIPY-Br dye molecules. At a power threshold density of 1.5 MW/cm 2, we observe the transition to a quasi-steady state, 1.2 ns long-lived, single-mode polariton lasing and the concomitant superlinear increase in photoluminescence, spectral line-narrowing, and energy blueshift.</p

Dataset for: Nano-second exciton-polariton lasing in organic microcavities

The experimental dataset used to create the figures in the paper A Putintsev, A Zasedatelev, KE McGhee, T Cookson, K Georgiou, D Sannikov, DG Lidzey, PG Lagoudakis, (2020). Nano-second exciton-polariton lasing in organic microcavities</span

Data for Room-temperature broadband polariton-lasing from a dye-filled microcavity

The experimental dataset used to create the figures in the paper Sannikov D., Yagafarov T., Georgiou K., Zasedatelev A., Baranikov A., Gai L., Shen Z., Lidzey D., Lagoudakis P., (2019). Room-temperature broadband polariton-lasing from a dye-filled microcavity. Advanced Optical Materials, https://doi.org/10.1002/adom.201900163</span

Dataset for: Mechanisms of blueshifts in organic polariton condensates

The experimental dataset used to create the figures in the paper Yagafarov T., Sannikov D., Zasedatelev A., Georgiou K., Baranikov A., Kyriienko O., Shelykh I., Gai L., Shen Z., Lidzey D., Lagoudakis P., (2019). Mechanisms of blueshifts in organic polariton condensates. Commun Phys 3, 18 (2020). https://doi.org/10.1038/s42005-019-0278-6</span

Single-photon nonlinearity at room temperature

The recent progress in nanotechnology1,2 and single-molecule spectroscopy3,4,5 paves the way for emergent cost-effective organic quantum optical technologies with potential applications in useful devices operating at ambient conditions. We harness a π-conjugated ladder-type polymer strongly coupled to a microcavity forming hybrid light–matter states, so-called exciton-polaritons, to create exciton-polariton condensates with quantum fluid properties. Obeying Bose statistics, exciton-polaritons exhibit an extreme nonlinearity when undergoing bosonic stimulation6, which we have managed to trigger at the single-photon level, thereby providing an efficient way for all-optical ultrafast control over the macroscopic condensate wavefunction. Here, we utilize stable excitons dressed with high-energy molecular vibrations, allowing for single-photon nonlinear operation at ambient conditions. This opens new horizons for practical implementations like sub-picosecond switching, amplification and all-optical logic at the fundamental quantum limit

Dataset for: Single-photon nonlinearity at room temperature.

The experimental dataset used to create the figures in the paper Zasedatelev A., Baranikov A., Sannikov D., Urbonas D., Scafirimuto F., Shishkov V., Andrianov E., Lozovik Yu., Scherf U., Stoferle T., Mahrt R., Lagoudakis P., Nature (2021). Single-photon nonlinearity at room temperature</span

Polariton condensation in an organic microcavity utilising a hybrid metal-DBR mirror

We have developed a simplified approach to fabricate high-reflectivity mirrors suitable for applications in a strongly-coupled organic-semiconductor microcavity. Such mirrors are based on a small number of quarter-wave dielectric pairs deposited on top of a thick silver film that combine high reflectivity and broad reflectivity bandwidth. Using this approach, we construct a microcavity containing the molecular dye BODIPY-Br in which the bottom cavity mirror is composed of a silver layer coated by a SiO2 and a Nb2O5 film, and show that this cavity undergoes polariton condensation at a similar threshold to that of a control cavity whose bottom mirror consists of ten quarter-wave dielectric pairs. We observe, however, that the roughness of the hybrid mirror—caused by limited adhesion between the silver and the dielectric pair—apparently prevents complete collapse of the population to the ground polariton state above the condensation threshold

A few-minute synthesis of CsPbBr₃ nanolasers with a high quality factor by spraying at ambient conditions

Inorganic cesium lead halide perovskite nanowires, generating laser emission in the broad spectral range at room temperature and low threshold, have become powerful tools for the cutting-edge applications in the optoelectronics and nanophotonics. However, to achieve high-quality nanowires with the outstanding optical properties, it was necessary to employ long-lasting and costly methods of their synthesis, as well as postsynthetic separation and transfer procedures that are not convenient for large-scale production. Here we report a novel approach to fabricate high-quality CsPbBr3 nanolasers obtained by rapid precipitation from dimethyl sulfoxide solution sprayed onto hydrophobic substrates at ambient conditions. The synthesis technique allows producing the well-separated nanowires with a broad size distribution of 2-50 μm in 5-7 min, being the fastest method to the best of our knowledge. The formation of nanowires occurs via ligand-assisted reprecipitation triggered by intermolecular proton transfer from (CH3)2CHOH to H2O in the presence of a minor amount of water. The XRD patterns confirm an orthorhombic crystal structure of the as-grown CsPbBr3 single nanowires. Scanning electron microscopy images reveal their regular shape and truncated pyramidal end facets, while high-resolution transmission electron microscopy ones demonstrate their single-crystal structure. The lifetime of excitonic emission of the nanowires is found to be 7 ns, when the samples are excited with energy below the lasing threshold, manifesting the low concentration of defect states. The measured nanolasers of different lengths exhibit pronounced stimulated emission above 13 μJ cm-2 excitation threshold with quality factor Q = 1017-6166. Their high performance is assumed to be related to their monocrystalline structure, low concentration of defect states, and improved end facet reflectivity.</p

CMS : the TriDAS Project Technical Design Report; v.1, the Trigger Systems

CM